1. Field of the Invention
The present invention relates to a feed feeding device used to manually feed sheets to various sheet processing apparatuses and image forming apparatuses as exemplified by copiers, facsimile apparatuses, and printers, and an image forming apparatus using the same.
2. Description of the Related Art
There have been conventionally known sheet feeding devices for feeding a sheet as a transfer material to a transfer device of an image forming apparatus as disclosed in Japanese Patent No. 3270613. This sheet feeding device is provided with a sheet cassette detachably attached to an apparatus main body of the image forming apparatus for storing a plurality of sheets of definite size, and a manual feeding portion disposed above this sheet cassette and used when small-size sheets such as postcards or sheets of indefinite size are manually fed one by one.
The manual feeding portion includes a plate-shaped sheet table on which sheets can be placed and a pair of cursors provided on this sheet table and adapted to guide the sheets so that the sheets can be fed straight. The sheet table is detachably attachable to the sheet cassette, and can change its posture between a vertical posture where the sheet table is accommodated in the sheet cassette and a horizontal posture where it is withdrawn from the sheet cassette. Upon manually feeding a sheet, the sheet table is withdrawn from the sheet cassette and set in the horizontal posture. Then, a spacing between the pair of cursors is adjusted in conformity with the width of the sheet, and the sheet is manually fed while being guided by these cursors. The manually fed sheet directly reaches a registration roller disposed at an upstream end of an image forming assembly, whereby the manual sheet feeding can be smoothly carried out. When no manual sheet feeding is carried out, the sheet table is accommodated in the vertical posture in the sheet cassette, wherefore there is no likelihood of a problem that the projecting sheet table stands in the way.
However, since the pair of cursors cannot be extended up to positions located inside the apparatus main body due to the set positions thereof in the sheet feeding device disclosed in Japanese Patent No. 3270613, these cursors are provided only at the side of a feed opening. Accordingly, no particular problem arises when a standard sheet of, e.g. A4 is manually fed, but a small-size sheet can be guided by the cursors only at a downstream position with respect to a sheet conveyance direction when the small-size sheet such as a postcard is manually fed. This makes it difficult to feed the sheet straight, resulting in a problem that the sheet may be obliquely fed.